Applicant is aware of several attempts in the prior art to attach magnets to the exterior of oil filters. In particular, Applicant is aware of U.S. Pat. No. 4,052,312 which issued to King for Strainer Magnets on Oct. 4, 1977, Canadian Patent Application No. 2,061,376 filed Feb. 17, 1992 and laid open Aug. 18, 1993, which application was filed by Perritt for his Magnetic Filter Strap Device, and Applicant is also aware of a device sold under the trade-mark "The Metal Arrester" by Metal Arrester Products of Hurst, Tex., U.S.A.
King teaches a magnetic oil filter strap which is pliable to be wrapped around the circumference of cylindrical oil filters, the ends of the strap resiliently fastened to each other by means of a spring. Perritt similarly discloses a pliable strap for encompassing the circumference of a cylindrical oil filter, the strap acting as a matrix to hold in radially spaced apart relation discrete magnets against the exterior casing of the oil filter. It is taught that the ends of the strap may be releasably fastened using conventional hook-and-loop type fasteners or that the flexible strap is made of resiliently stretchable material and is provided with a non-adjustable joining device at the strap ends whereby the strap may be stretched to fit around the exterior casing of the oil filter. The metal arrester device is a large magnet in a plastic housing that slides onto the end of the oil filter. The metal arrester device is a large magnet in a plastic housing that slides onto the end of an existing oil filter.
The various prior art devices address means for securing magnetic elements to the exterior casing of an oil filter and also to means for securing such magnetic elements for oil filters of various sizes. The problem that has arisen with such prior art devices is that in some instances it is difficult is to fit an annular band, sleeve or the like around the exterior casing of an installed automotive oil filter due to small clearance between the casing of the oil filter and other obstructing structure within the engine compartment. This also occurs when replacement oil filters are used in an automobile and the replacement oil filter diameter is slightly larger than that of the filter being replaced.
Thus it is an object of the present invention to provide individual non-magnetic housings for housing discrete magnetic elements, which housings and magnetic elements do not rely on an annular band, strap or sleeve, or on any band or strap at all in order to be secured to the exterior of a metal oil casing on a piece of machinery such as a metal oil filter casing or transmission, differential, gearbox or like oil bathed machinery enclosed in a metal casing. The individual magnetic element housings of the present invention allow for the distribution of magnetic elements around an oil casing, and in particular the casing of an installed oil filter, without the requirement of forcing a band or strap or annular sleeve into an insufficient clearance space between the oil casing or filter casing and other structures. Thus, the magnetic elements may be placed around, or longtidunally along, the casing or filter wall or even placed on the bottom of casing or filter, to minimize damage to the magnetic element housing and magnetic element when removing or repairing the oil casing or oil filter or when installing a new oil casing or filter.
A further object of the invention is to provide a magnetic element housing which will only minimally attenuate, with respect to metal particles in the oil, the effects of a magnetic element placed against the exterior of an oil filter housing, and which will in respect of an opposed side of such a magnetic element significantly attenuate the effects of the magnetic element acting upon metal hand tools inadvertently brought into close proximity with the magnetic element housing.